Computing devices (e.g., mobile phones, tablet computers, etc.) may provide a graphical keyboard as part of a graphical user interface for composing text using a presence-sensitive display. For instance, a presence-sensitive display of a computing device may output a graphical, or soft, keyboard that permits the user to enter data by tapping (or otherwise indicating) keys displayed at the presence-sensitive display. The graphical keyboard may enable a user of the computing device to compose and edit text included in, for example, an e-mail, a text message, a document, etc.
Some computing devices also include an auto-correction system to detect and correct spelling and grammar errors within user-entered text. Some auto-correction systems, however, may fail to detect non-spelling or non-grammar errors within the text and/or may make erroneous automatic corrections. Some auto-correction systems may fail to detect such errors because these systems perform exact word matching for misspelled dictionary words within the text. Consequently, such auto-detection systems may not detect an error so long as the entered text includes a valid word (e.g., a word found within a dictionary employed by the system). In addition, if a user intentionally types a non-dictionary word, the auto-correction system may automatically (and contrary to the user's intent) replace the misspelled word with a dictionary word.